Renuka Khatik

Pharmacokinetics study of arteether loaded solid lipid nanoparticles: an improved oral bioavailability in rats.

Arteether (ART), an artemisinin derivative, is a life saving drug for multiple drug resistant malaria. It has a deliverance effect in Falciparum malaria and cerebral malaria. We have prepared solid lipid nanoparticles (SLN) by high pressure homogenization (HPH) technique. ART-loaded SLN (ART-SLN) has been produced reproducibly with homogeneous particle size. ART-SLN was characterized for their size measured by Zetasizer Nano-ZS, Malvern, UK and by high resolution transmission electron microscopy (HR-TEM) and which was found to be 100 ± 11.2 nm. The maximum percentage entrapment efficiency (%EE) determined with the high-performance liquid chromatography (HPLC) has been found to be 69 ± 4.2% in ART-SLN-3. The release pattern from ART-SLN revealed that the release of ART is slow but time-dependent manner, which is desirable as it will help to protect the acid degradation of ART in stomach. The percentage cytotoxicity of blank SLN has been found within the acceptable range. The pharmacokinetics results indicated that ART-SLN-3 absorption has been significantly enhanced in comparison to ART in aqueous suspension and ART in ground nut oil (GNO) in rats. The % relative bioavailability (RB%) of ART-SLN to the ART in GNO and ART in aqueous suspension in rats was 169.99% and 7461%, respectively which was found to be significantly high in both the cases. From the results, it can be concluded that ART-SLN offers a new approach to improve the oral bioavailability of ART.

Development of targeted 1,2-diacyl-sn-glycero-3-phospho-l-serine-coated gelatin nanoparticles loaded with amphotericin B for improved in vitro and in vivo effect in leishmaniasis.

Objective: The principle objective of this study was to develop 1,2-diacyl-sn-glycero-3-phospho-l-serine (PS)-coated gelatin nanoparticles (GNPs) bearing amphotericin B (AmB) for specific targeting to the macrophages involved in visceral leishmaniasis (VL). Method: The two-step desolvation method has been used for the preparation of GNPs with AmB, which was further coated with PS (PS-AmB-GNPs). The targeting potential of it was compared with uncoated AmB-loaded GNPs (AmB-GNPs) for in vitro and in vivo macrophage uptake. Results: The results of flow cytometric data revealed enhanced uptake of PS-AmB-GNPs in J774A.1 macrophage cell lines compared with AmB-GNPs. In vivo organ distribution studies in Wistar rats demonstrated a significantly higher extent of accumulation of PS-AmB-GNPs compared with AmB-GNPs in macrophage-rich organs, particularly in liver and spleen. The in vivo anti-leishmanial activity of plain AmB, AmB-GNPs and PS-AmB-GNPs was tested against VL in Leishmania donovani-infected hamsters. Highly significant anti-leishmanial activity (p < 0.05 compared with AmB-GNPs) was observed with PS-AmB-GNPs, causing 85.3 ± 7.89% inhibition of splenic parasitic burden. AmB-GNPs and plain AmB caused only 71.0 ± 3.87 and 50.5 ± 5.12% parasite inhibitions, respectively, in Leishmania-infected hamsters (p < 0.05 for PS-AmB-GNPs versus plain AmB and AmB-GNPs versus plain AmB). Conclusion: The objective of the preparation was achieved and high accumulation of AmB in liver and spleen has been found, which resulted in enhanced anti-leishmanial activity.

Development, characterization and toxicological evaluations of phospholipids complexes of curcumin for effective drug delivery in cancer chemotherapy

Abstract The purpose of this study was to prepare and characterize the complexes between curcumin (CU) phosphatidylcholine (PC) and hydrogenated soya phosphatidylcholine (HSPC) and to evaluate their anticancer activity. These CU–PC and CU–HSPC complexes (CU–PC-C and CU–HSPC-C) were evaluated for various physical parameters like Fourier transform infrared spectroscopy, melting point, solubility, scanning electron microscopy and the in vitro drug release study. These data confirmed the formation of phospholipids complexes. The in vitro hemolysis study showed that the complex was non-hemolytic. The anti-cancer potential of the complexes was demonstrated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay in MCF-7 cell line. This increase may be due to the amphiphilic nature of the complexes, which significantly enhances the water and lipid solubility of the CU. Unlike the free CU (which showed a total of only 90% drug release at the end of 8 h), complex showed around 40–60% release at the end of 8 h in dissolution studies. It showed that (when given in equimolar doses) complexes have significantly decreased the amount of CU available for absorption as compared with CU-free drug. Both CU-PC-C and CU-HSPC-C were found to be non-toxic at the dose equivalent to 2000 mg/kg of body weight of CU in the toxicity study. Acute and subacute toxicity studies confirmed the oral safety of the formulation. A series of genotoxicity studies was conducted, which revealed the non-genotoxicity potential of the developed complexes. Thus, it can be concluded that the phospholipid complexes of CU may be a promising candidate in cancer therapy.

Development of 4-sulfated N-acetyl galactosamine anchored chitosan nanoparticles: a dual strategy for effective management of Leishmaniasis

The present investigation reports the modification of chitosan nanoparticles with a ligand 4-sulfated N-acetyl galactosamine (4-SO4GalNAc) for efficient chemotherapy in leishmaniasis (SCNPs) by using dual strategy of targeting. These (SCNPs) were loaded with amphotericin B (AmB) for specific delivery to infected macrophages. Developed AmB loaded SCNPs (AmB-SCNPs) had mean particle size of 333 ± 7 nm, and showed negative zeta potential (-13.9 ± 0.016 mV). Flow cytometric analysis revealed enhanced uptake of AmB-SCNPs in J774A.1, when compared to AmB loaded unmodified chitosan NPs (AmB-CNPs). AmB-SCNPs provide significantly higher localization of AmB in liver and spleen as compared to AmB-CNPs after i.v. administration. The study stipulates that 4-SO4GalNAc assures of targeting, resident macrophages. Highly significant anti-leishmanial activity (P<0.05 compared with AmB-CNPs) was observed with AmB-SCNPs, causing 75.30 ± 3.76% inhibition of splenic parasitic burdens. AmB-CNPs and plain AmB caused only 63.89 ± 3.44% and 47.56 ± 2.37% parasite inhibition, respectively, in Leishmania-infected hamsters (P<0.01 for AmB-SCNPs versus plain AmB and AmB-CNPs versus plain AmB).

Self-nanoemulsifying drug delivery systems (SNEDDS) for oral delivery of arteether: pharmacokinetics, toxicity and antimalarial activity in mice

The aim of the study was to develop oral arteether (AE) nano formulations, to investigate their effects in rats, and for the complete and effective treatment of Plasmodium yoelii nigeriensis infected mice at a reduced dose by increasing the relative bioavailability. Nano-formulations of arteether have been developed. The relative bioavailability (RB%) was assessed by calculating individual Area under curve (AUC) AUC0–t, AUC0–∞ and Cmax values. Haematological and biochemical parameters were estimated in rats and sections of brain and peripheral organs were analyzed for histopathological changes. The formulations were tested for antimalarial efficacy and safety in Plasmodium yoelii nigeriensis infected swiss mice. The AUC for lipid formulations (AUC0–t 4.98 ± 0.79 h μg ml−1) and AUC0–∞ (5.02 ± 0.80 h μg ml−1) was significantly higher (p < 0.05) than for AE in ground nut oil (GNO) and AE in aqueous suspension. The Cmax was also significantly higher for all the formulations. The RB% has been found to be significantly higher (257%) in the formulations than for AE in GNO. No considerable changes have been monitored in the serum biochemical parameters of rats. These formulations have been found to be highly effective for the treatment of Plasmodium yoelii nigeriensis infected swiss mice, even at the lower dose of 12.5 mg kg−1 × 5 days. Overall the developed formulations are safe, provide a non-toxic platform for further clinical studies, and can be used in artemisinin-based combination therapies (ACTs).

Potential in vitro and in vivo colon specific anticancer activity in a HCT-116 xenograft nude mice model: targeted delivery using enteric coated folate modified nanoparticles

The aim of this study was to develop a drug delivery system for specific targeting in colon cancer treatment. We have developed a Eudragit S-100 (ES) coated folic acid (FA) conjugated gliadin (Gd) delivery system for the effective targeting of overexpressed folate receptors (FRs) in colon cancer. The FA conjugate with Gd (FA–Gd) was synthesized and characterized using FTIR and 1H NMR, and this developed conjugate was used to prepare curcumin (CU) loaded nanoparticles (NPs) by a desolvation method. FA–CU–GdNPs were further coated with ES and ES–FA–CU–GdNPs were obtained. The ES–FA–CU–GdNPs were also capable of inducing cell caspase dependent apoptosis in Caco-2 cell lines and exhibited DNA intercalating activity. In therapeutic experiments the ES–FA–CU–GdNPs were administered orally to HCT-116 tumor-bearing nude mice. In vivo bio-distribution data showed that ES–FA–CU–GdNPs had delivered the maximum amount of NPs to the colon and tumor after 12 hours, reflecting its targeting potential for the colon and tumor. A gamma scintigraphy study suggested that ES–FA–CU–GdNPs remain intact at low pH and released NPs slowly at pH 7.4 in the colon. This study provides evidence that ES–FA–CU–GdNPs hold the promise to address overexpressed FRs in colorectal cancer and were found to be safe for oral administration for a prolonged duration.

Arteether nanoemulsion for enhanced efficacy against Plasmodium yoelii nigeriensis malaria: An approach by enhanced bioavailability

The present work is focused on the preparation of nanoemulsions (NEs) loaded with arteether (ART) for its enhanced efficacy against malaria parasites. ART-NEs have been prepared using high pressure homogenization (HPH) technique with the aim of improving its solubility and thus its bioavailability. ART-NEs were optimized in terms of pressure and number of cycles. Globule size and size distributions were chosen as quality parameters. The maximum drug loading was achieved up to 93 ± 7.4% with globule size 156 ± 10.2 nm and zeta potential of -23.3 ± 3.4 mV. The developed ART-NEs were found to be stable in terms of globule size and size distribution at different pH. The in vitro release profile of the ART-NEs showed 62% drug release within 12h. The percentage cell viability of blank NEs were within acceptable limits. A sensitive assay method for the determination of ART in rat plasma by liquid chromatography-mass spectrometry (LC-MS) was employed after oral administration of ART-NEs. The pharmacokinetic study showed significantly enhanced bioavailability of ART in ART-NE-V. The area under curve (AUC) of ART-NE-V was AUC0-t 1988.411 ± 119.66 h ng/ml which was significantly higher (p<0.05) than ART in ground nut oil (GNO) AUC0-t 671.852 ± 187.05 h ng/ml. The Cmax of ART-NE-V (1506 ± 161.22 ng/ml) was also significantly higher (p<0.05) than ART in GNO (175.2 ± 16.54 ng/ml) and ART given intramuscularly (IM) (278.05 ± 38.59 ng/ml). The ART-NE-V was having significantly high antimalarial efficacy and survival rate of mice giving 80% cure rate at 12.5 mg/kg for 5 days in comparison to 30% cure rate of ART in GNO at the same daily dose and it was also comparable to the 100% cure rate at 12.5 mg/kg for 5 days for ART given intramuscularly. In conclusion ART-NE can be a promising oral delivery system for ART.

Validation of RP-HPLC Method for Simultaneous Quantification of Bicalutamide and Hesperetin in Polycaprolactone-Bicalutamide-Hesperetin-Chitosan Nanoparticles

Bicalutamide is a non-steroidal anti-androgen drug used for the treatment of androgen-dependent prostate cancer. Hesperetin is a natural bioflavonoid that can be used in combination with bicalutamide to improve efficacy and decrease tolerance. The aim of the present work was to develop and validate a simple, sensitive, rapid reverse phase-high performance liquid chromatographic method for simultaneous estimation of bicalutamide and hesperetin. The validation parameters such as specificity, linearity, precision and accuracy, limit of detection (LOD) and limit of quantification (LOQ) were determined according to International Conference on Harmonization ICH Q2 (R1) guidelines. Chromatographic separation was achieved on Lichrocart(®) CN column (250 × 4 mm, 5 µm, MERCK) with isocratic elution. The retention times and detection wavelength, for hesperetin and bicalutamide were 4.28 min, 288 nm and 5.90 min, 270 nm respectively. The intra-day and inter-day assay precision and accuracy were found to be <2% over linearity of 50-2000 ng/mL with R(2) 0.999. LOD and LOQ, of bicalutamide and hesperetin was 14.70, 44.57 ng/mL and 16.11, 48.84 ng/mL, respectively. The method was successfully applied for encapsulation efficiency and drug release studies from bicalutamide and hesperetin loaded nanoparticles.